lpc17xx_wdt.c

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/***********************************************************************/
/* Peripheral group ----------------------------------------------------------- */
/* Includes ------------------------------------------------------------------- */
#include "lpc17xx_wdt.h"
#include "lpc17xx_clkpwr.h"
#include "lpc17xx_pinsel.h"


/* If this source file built with example, the LPC17xx FW library configuration
 * file in each example directory ("lpc17xx_libcfg.h") must be included,
 * otherwise the default FW library configuration file must be included instead
 */
#ifdef __BUILD_WITH_EXAMPLE__
#include "lpc17xx_libcfg.h"
#else
#include "lpc17xx_libcfg_default.h"
#endif /* __BUILD_WITH_EXAMPLE__ */


#ifdef _WDT

/* Private Functions ---------------------------------------------------------- */

static uint8_t WDT_SetTimeOut (uint8_t clk_source, uint32_t timeout);

/********************************************************************/
static uint8_t WDT_SetTimeOut (uint8_t clk_source, uint32_t timeout)
{

    uint32_t pclk_wdt = 0;
    uint32_t tempval = 0;

    switch ((WDT_CLK_OPT) clk_source)
    {
    case WDT_CLKSRC_IRC:
        pclk_wdt = 4000000;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));
        // Check if it valid
        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            LPC_WDT->WDTC = tempval;
            return  SUCCESS;
        }

        break;

    case WDT_CLKSRC_PCLK:

        // Get WDT clock with CCLK divider = 4
        pclk_wdt = SystemCoreClock / 4;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_4);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return SUCCESS;
        }

        // Get WDT clock with CCLK divider = 2
        pclk_wdt = SystemCoreClock / 2;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_2);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return  SUCCESS;
        }

        // Get WDT clock with CCLK divider = 1
        pclk_wdt = SystemCoreClock;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));

        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_1);
            LPC_WDT->WDTC = (uint32_t) tempval;
            return  SUCCESS;
        }
        break ;


    case WDT_CLKSRC_RTC:
        pclk_wdt = 32768;
        // Calculate TC in WDT
        tempval  = (((pclk_wdt) / WDT_US_INDEX) * (timeout / 4));
        // Check if it valid
        if ((tempval >= WDT_TIMEOUT_MIN) && (tempval <= WDT_TIMEOUT_MAX))
        {
            LPC_WDT->WDTC = (uint32_t) tempval;
            return  SUCCESS;
        }

        break;

// Error parameter
        default:
            break;
}

    return ERROR;
}

/* End of Private Functions --------------------------------------------------- */


/* Public Functions ----------------------------------------------------------- */
/*********************************************************************/
void WDT_Init (WDT_CLK_OPT ClkSrc, WDT_MODE_OPT WDTMode)
{
    CHECK_PARAM(PARAM_WDT_CLK_OPT(ClkSrc));
    CHECK_PARAM(PARAM_WDT_MODE_OPT(WDTMode));
    CLKPWR_SetPCLKDiv (CLKPWR_PCLKSEL_WDT, CLKPWR_PCLKSEL_CCLK_DIV_4);

    //Set clock source
    LPC_WDT->WDCLKSEL &= ~WDT_WDCLKSEL_MASK;
    LPC_WDT->WDCLKSEL |= ClkSrc;
    //Set WDT mode
    if (WDTMode == WDT_MODE_RESET){
        LPC_WDT->WDMOD |= WDT_WDMOD(WDTMode);
    }
}

/*********************************************************************/
void WDT_Start(uint32_t TimeOut)
{
    uint32_t ClkSrc;

    ClkSrc = LPC_WDT->WDCLKSEL;
    ClkSrc &=WDT_WDCLKSEL_MASK;
    WDT_SetTimeOut(ClkSrc,TimeOut);
    //enable watchdog
    LPC_WDT->WDMOD |= WDT_WDMOD_WDEN;
    WDT_Feed();
}

/********************************************************************/
FlagStatus WDT_ReadTimeOutFlag (void)
{
    return ((FlagStatus)((LPC_WDT->WDMOD & WDT_WDMOD_WDTOF) >>2));
}

/********************************************************************/
void WDT_ClrTimeOutFlag (void)
{
    LPC_WDT->WDMOD &=~WDT_WDMOD_WDTOF;
}

/********************************************************************/
void WDT_UpdateTimeOut ( uint32_t TimeOut)
{
    uint32_t ClkSrc;
    ClkSrc = LPC_WDT->WDCLKSEL;
    ClkSrc &=WDT_WDCLKSEL_MASK;
    WDT_SetTimeOut(ClkSrc,TimeOut);
    WDT_Feed();
}


/********************************************************************/
void WDT_Feed (void)
{
    // Disable irq interrupt
    __disable_irq();
    LPC_WDT->WDFEED = 0xAA;
    LPC_WDT->WDFEED = 0x55;
    // Then enable irq interrupt
    __enable_irq();
}

/********************************************************************/
uint32_t WDT_GetCurrentCount(void)
{
    return LPC_WDT->WDTV;
}

#endif /* _WDT */

/* --------------------------------- End Of File ------------------------------ */